Posts about Duke

Tropical Lizards Can Solve Novel Problems and Remember the Solutions

Brainy Lizards Pass Tests for Birds

[Duke biologist Manuel Leal] tested the lizards using a wooden block with two wells, one that was empty and one that held a worm but was covered by a cap. Four lizards, two male and two female, passed the test by either biting the cap or bumping it out of the way.

The lizards solved the problem in three fewer attempts than birds need to flip the correct cap and pass the test, Leal said. Birds usually get up to six chances a day, but lizards only get one chance per day because they eat less. In other words, if a lizard makes a mistake, it has to remember how to correct it until the next day

Leal’s experiment “clearly demonstrates” that when faced with a situation the lizards had never experienced, most of them were able to devise a way to solve the problem. Their ability to “unlearn” a behavior, a skill that some mammalian species have difficulty in, is the mark of a cognitively advanced animal, said Jonathan Losos, a biologist at Harvard who was not involved in the study.

To see if the lizards could reverse this association, Leal next placed the worm under the other cap. At first, all the lizards bumped or bit the formerly lucrative blue cap. But after a few mistakes, two of the lizards figured out the trick. “We named these two Plato and Socrates,” Leal said.

It is very cool to see what scientists keep learning about animals.

Related: Insightful Problem Solving in an Asian ElephantBird Using Bread as Bait to Catch FishCrows Transferring Their Understanding to Novel ProblemDolphins Using Tools to Hunt

Majority of Clinical Trials Don’t Provide Meaningful Evidence

The largest comprehensive analysis of ClinicalTrials.gov finds that clinical trials are falling short of producing high-quality evidence needed to guide medical decision-making.

The analysis, published today in the Journal of the American Medical Association, found the majority of clinical trials is small, and there are significant differences among methodical approaches, including randomizing, blinding and the use of data monitoring committees.

This is a critical issue as medical studies continue to leave quite a bit to be desired. Even more importantly the failure to systemically study and share evidence of effectiveness once treatments are authorized leaves a great deal to be desired. On top of leaving quite a bit to be desired, the consequences are serious. If we make mistakes for example in how we date fossils it matters but it is unlikely to cause people their lives or health. Failure to adequately manage and analyze health care experiments may very well cost people their health or lives.

“Our analysis raises questions about the best methods for generating evidence, as well as the capacity of the clinical trials enterprise to supply sufficient amounts of high quality evidence to ensure confidence in guideline recommendations,” said Robert Califf, MD, first author of the paper, vice chancellor for clinical research at Duke University Medical Center, and director of the Duke Translational Medicine Institute.

The analysis was conducted by the Clinical Trials Transformation Initiative (CTTI), a public-private partnership founded by the Food and Drug Administration (FDA) and Duke. It extends the usability of the data in ClinicalTrials.gov for research by placing the data through September 27, 2010 into a database structured to facilitate aggregate analysis.

Related: Statistical Errors in Medical StudiesHow to Deal with False Research FindingsMedical Study Integrity (or Lack Thereof)

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Electrifying a New Generation of Engineers

Electrifying a New Generation of Engineers

Ybarra’s K-12 education efforts began informally in 1993 while he was a newly arrived professor at Duke, toting lasers and other captivating bits of engineering equipment to local schools to drum up excitement for science and engineering and an array of programs grew from there.

Based on his growing awareness of the value of hands-on learning, Ybarra was longing for a way to help get more hands-on learning into the classroom. A few years later, in 1999, he was able to secure his first significant grant in the area. With support from the National Science Foundation Ybarra formalized his interactions with local schools by establishing a fellowship program that would put Duke engineering students in the classrooms to vastly expand the number of schools impacted.

To date, Ybarra’s programs have impacted more than 150,000 kids, and with so many programs now in place and spreading, that number increases by about 50,000 students per year. But personal stories, rather than numbers, are what Ybarra finds most gratifying. “When students contact me years later to tell me that the experiences they had in my programs inspired them to pursue a career in engineering or one of the sciences, it gives me a very deep sense of satisfaction.”

Related: Engineering K-PhDEngineering a Better Blood Alcohol SensorPromoting Science and EngineeringYale Cultivates Young ScientistsHigh School Students in USA, China and India

Bird Brain Language Research

Molecular Mapping of Movement-Associated Areas in the Avian Brain: A Motor Theory for Vocal Learning Origin

Vocal learning is a critical behavioral substrate for spoken human language. It is a rare trait found in three distantly related groups of birds-songbirds, hummingbirds, and parrots. These avian groups have remarkably similar systems of cerebral vocal nuclei for the control of learned vocalizations that are not found in their more closely related vocal non-learning relatives. These findings led to the hypothesis that brain pathways for vocal learning in different groups evolved independently from a common ancestor but under pre-existing constraints. Here, we suggest one constraint, a pre-existing system for movement control.

Using behavioral molecular mapping, we discovered that in songbirds, parrots, and hummingbirds, all cerebral vocal learning nuclei are adjacent to discrete brain areas active during limb and body movements. Similar to the relationships between vocal nuclei activation and singing, activation in the adjacent areas correlated with the amount of movement performed and was independent of auditory and visual input.

Based upon these findings, we propose a motor theory for the origin of vocal learning, this being that the brain areas specialized for vocal learning in vocal learners evolved as a specialization of a pre-existing motor pathway that controls movement.

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